KR101147971B1 - Low-k siloxane passivation layer composition - Google Patents

Abstract

The present invention relates to a low dielectric constant siloxane protective film composition by a fluorinated organic oligosiloxane prepared by a sol-gel reaction that can be used as a passivation layer of a thin film transistor. The fluorinated organic oligosiloxane provides a low-permittivity siloxane protective film composition capable of solution processing and having high transparency, excellent thermal stability, low dielectric constant, low leakage current, flatness, and adhesiveness even in a low temperature curing process of 200 degrees or less.

Description

Low-k siloxane passivation layer composition

The present invention relates to a low dielectric constant siloxane protective film composition for passivation layers of thin film transistors with fluorinated organic oligosiloxanes produced by a sol-gel reaction. The fluorinated organic oligosiloxane can be a solution process and provides a low-k siloxane protective film composition having properties of high transparency, high thermal stability, low dielectric constant, low leakage current, flatness, and adhesion even in a low temperature curing process.

Thin film transistors are widely used in display fields such as LCD, OLED, and e-paper. In general, the thin film transistors used in the display field are disposed at each pixel, thereby enabling high-speed response characteristics of the display and enabling a large number of pixels, thereby greatly contributing to the realization of high performance / high performance next-generation displays comparable to the CRT (Cathode Ray Tube). Could. However, high performance such as electrodes, semiconductor active layers, gate insulating layers, and protective films used as components of thin film transistors has been required to increase the size and resolution of displays implemented using thin film transistors.

The passivation layer used as a component of the thin film transistor is a key material for implementing a thin film transistor which improves the reliability of the semiconductor active layer of the thin film transistor and serves to insulate the electrodes used in the thin film transistor.

Conventionally, inorganic films such as silicon nitride (SiNx) and silicon oxide (SiOx) have been applied as a protective film of thin film transistors for excellent insulating properties and reliability of semiconductor active layers. However, the inorganic film used as the protective film has low transparency, which lowers the aperture ratio of the display, thereby preventing the display of high resolution and high brightness. In addition, due to their high dielectric constant, signal delay between the electrode and the wiring for implementing the thin film transistor is lowered, thereby lowering the response speed of the display, thereby making it difficult to implement a high-performance display. In addition, the vacuum deposition method used to deposit silicon nitride (SiNx) or silicon oxide (SiOx) is difficult to match the thickness uniformity in a large area, which is limited to use in large area displays.

Recently, BCB (benzocyclobutene) and the like have been attempted as an organic protective film for thin film transistors using a solution process to realize high resolution, high brightness, high performance, and large area display. The organic protective film has a low dielectric constant (<3.0) and excellent insulating properties, but since the heat treatment temperature is 250 degrees or more, the active layer may be degraded by the process temperature of the protective film, and thus it is not an effective method for the organic protective film. (Prog. Polym. Sci. 26. 3-65 (2001))

On the other hand, in order to realize high resolution, high brightness, high performance, and large area display, a research on siloxane protective film that enables low temperature solution process as a protective film for thin film transistor using a solution process is being conducted. The siloxane protective film for the thin film transistor has a low temperature process of 200 degrees or less, excellent insulating properties, and high transparency, and is suitable as a protective film for thin film transistors. (SID 2008 DIGEST pp140 ~ 142) However, the conventional siloxane protective film for thin film transistor has the disadvantage that it can prevent high performance display due to the relatively high dielectric constant (> 3.0), so it has low dielectric constant (<3.0) and low temperature below 200 degrees. There is a need to develop a low-rate siloxane protective film composition capable of solution processing and having excellent insulation properties, high transparency, flatness and adhesion.

The present invention was derived to solve the above-mentioned problems of the prior art, and is produced by a sol-gel reaction capable of low dielectric constant, excellent insulation properties, high transparency, good thermal stability, flatness, adhesiveness, low temperature, and solution process. An object of the present invention is to provide a low dielectric constant siloxane protective film composition for passivation layers of thin film transistors using fluorinated organic oligosiloxanes.

In order to achieve the above object, the present invention provides a fluorinated organic oligosiloxane prepared by a sol-gel reaction between an organoalkoxysilane having an asymmetric structure, an alkoxy fluoride silane and an organosilane or an organoalkoxysilane having a symmetrical structure. A low dielectric constant siloxane protective film composition for a passivation layer of a thin film transistor is provided.

Fluorinated organoligosiloxane contained in the low dielectric constant siloxane protective film composition according to the present invention is prepared through a sol-gel reaction. In particular, the fluorinated organic oligosiloxane according to the present invention is prepared by a sol-gel reaction between an organoalkoxysilane having an asymmetric structure, an alkoxy fluoride silane and an organosilane or an organoalkoxysilane having a symmetrical structure.

The low dielectric constant siloxane protective film composition for the passivation layer of the thin film transistor containing the fluorinated organic oligosiloxane of the present invention has excellent insulation properties, thermal stability, and high transparency by nano-sized oligosiloxane formed by sol-gel reaction. .

The low dielectric constant siloxane protective film composition has surprisingly low dielectric constant of 3.0 or less by combination of organic silanol and organic alkoxysilane having a symmetrical structure with the reduction of electron polarization by the alkoxysilane fluoride. In addition, the organic functional group of the organic alkoxysilane enables low temperature and solution process, and has excellent flatness and adhesive properties.

As a result, the low dielectric constant siloxane protective film composition of the present invention, unlike the conventional technology, the protective film of the thin film transistor that satisfies all the characteristics of low dielectric constant, excellent insulation, high transparency, excellent thermal stability, flatness, adhesion, low temperature and solution process It is possible to provide a (passivation layer) to complete the present invention.

Hereinafter, the present invention will be described in more detail.

Fluorinated organic oligosiloxanes for the preparation of low dielectric constant siloxane protective film compositions for passivation layers of thin film transistors are prepared through sol-gel reactions. The reaction scheme below represents a general sol-gel reaction for preparing fluorinated organoligosiloxanes.

The following scheme is a chemical formula of hydrolysis-condensation of alkoxysilanes in the presence of water (single sol-gel reaction).

As can be seen from the above reaction scheme, the alkoxy group of the starting material alkoxysilane is hydrolyzed together with water to form a hydroxyl group, and a siloxane bond is formed by condensation reaction with an alkoxy group or hydroxyl group of another monomer to form an oligosiloxane.

Another sol-gel reaction of the following reaction formula expresses the condensation reaction between silanol modified with hydroxyl group and alkoxysilane modified with alkoxy group without addition of water (non-single sol-gel reaction).

As can be seen from the above reaction scheme, condensation reaction of hydroxyl group of silanol as starting material and alkoxy group of alkoxysilane forms siloxane bond to form oligosiloxane.

When the fluorinated oligosiloxane is prepared in order to prepare a low dielectric constant siloxane protective film composition for a passivation layer of a thin film transistor using the general hydrosol-gel reaction, the siloxane bond is added through a hydrolysis-condensation reaction in which water is added to the alkoxysilane. Since this is formed, it is possible to promote the sol-gel reaction by adding a catalyst.

Available catalysts include acetic acid, phosphoric acid, sulfuric acid, hydrochloric acid, nitric acid, chlorosulfonic acid, para-toluic acid, trichloroacetic acid, polyphosphoric acid, acidic catalysts such as phylloic acid, iodic acid, tartaric acid, perchloric acid or ammonia, sodium hydroxide, n Base catalysts such as butylamine, di-n-butylamine, tri-n-butylamine, imidazole, ammonium perchlorate, potassium hydroxide, barium hydroxide, and ion exchange resins such as Amberite IPA-400 (Cl) Can be used. The addition amount of the catalyst is not particularly limited, and it is sufficient to add 0.0001 to 10 parts by weight based on 100 parts by weight of the alkoxysilane. The reaction is sufficient to stir 6 to 24 hours at room temperature, and to promote the reaction rate and to proceed with the complete condensation reaction, induction of hydrolysis-condensation reaction at 0 ~ 100 ^o C preferably 60 ^o C for 6 hours Oligosiloxanes can be formed.

In addition, in the oligosiloxane hybrid material prepared through the hydrolysis-condensation reaction, by-product alcohol and water remaining after the reaction are present, which is 0 ^o C to 120 ^o C preferably -0.1 MPa, 60 ^o under atmospheric pressure and reduced pressure. It can remove by performing for 30 minutes on C conditions.

Condensation reaction between the hydroxyl group of silanol and the alkoxy group of alkoxysilane when fluorinated oligosiloxane is prepared for the preparation of low dielectric constant siloxane protective layer composition for passivation layer of thin film transistor using the general non-aqueous sol-gel reaction Since oligosiloxanes are formed throughout, the addition of a catalyst can lower the reaction temperature and promote the sol-gel reaction. As a usable catalyst, metal hydroxides such as barium hydroxide and strontium hydroxide may be used. The addition amount of the catalyst is not particularly limited and it is sufficient to add 0.0001 to 10 parts by weight based on the total silane content. The reaction is sufficient to stir for 6 to 72 hours at room temperature, and in order to promote the reaction rate and to proceed with a complete condensation reaction, induce condensation reaction at 0 to 100 ^o C preferably 60 ^o C for 6 hours to form siloxane bonds. Can be formed.

The organoalkoxysilane having the asymmetrical structure may be used by selecting one or more from Formula 1 below. The organoalkoxysilane has an organic chain substituted with an alkoxy group and a functional group or an unsubstituted organic chain.

[Formula 1]

[In Formula 1, R ¹ is (C1-C20) alkyl, (C3-C8) cycloalkyl, (C3-C8) alkyl substituted with (C3-C8) cycloalkyl, (C2-C20) alkenyl, (C2 ~ C20) Alkynyl and any one selected from the group consisting of (C6 ~ C20) aryl, acrylic group, methacryl group, aryl group, amino group, mercapto group, ether group, ester group, sulfone group, nitro group, hydroxide May have at least one thermosetting or photocurable functional group selected from the group consisting of a period, a cyclobutene group, a carbonyl group, a carboxyl group, an alkyd group, a urethane group, a vinyl group, a nitrile group, an epoxy group and an alicyclic epoxy group; R ² is straight or branched chain (C 1 -C 7) alkyl.]

More specifically, the asymmetric organoalkoxysilane is 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, propylethyltrimethoxysilane, ethyltriethoxysilane, vinyltri Methoxysilane, vinyltriethoxysilane, aryltrimethoxysilane, aryltriethoxysilane, vinyltripropoxysilane, phenyltrimethoxysilane, N- (3-acryloxy-2-hydroxypropyl) -3 -Aminopropyltriethoxysilane, N- (3-acryloxy-2-hydroxypropyl) -3-aminopropyltrimethoxysilane, N- (3-acryloxy-2-hydroxypropyl) -3-amino Propyltripropoxysilane, (acryloxymethyl) phenethyltrimethoxysilane, 3-acryloxypropyltri Methoxysilane, 3-acryloxypropyltriethoxysilane, 3-acryloxypropyltripropoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3 -(Meth) acryloxypropyltripropoxysilane, N- (aminoethyl) -3-aminopropyl trimethoxysilane, N- (2-aminoethyl) -3-aminopropyl triethoxysilane, 3-aminopropyl At least one selected from the group consisting of trimethoxysilane, 3-aminopropyltriethoxysilane, chloropropyltrimethoxysilane, chloropropyltriethoxysilane, phenyltrimethoxysilane, and phenyltriethoxysilane can be used. However, the present invention is not limited thereto.

The alkoxy fluoride silane having the asymmetric structure may be used by selecting one or more from the following formula (2). The alkoxy fluoride silane has an organic chain substituted with an alkoxy group and a fluorinated functional group.

[Formula 2]

[In Formula 2, R ³ is (C 1 -C 20) alkyl substituted with (C 1 -C 20) alkyl, (C 3 -C 8) cycloalkyl, (C 3 -C 8) cycloalkyl containing a fluoro group, (C 2- C20) alkenyl, (C2 ~ C20) alkynyl and (C6 ~ C20) aryl group; R ⁴ Is linear or branched (C1-C7) alkyl.]

More specifically, the asymmetric alkoxy fluoride silane is (heptadecafluoro-1,1,2,2-tetrahydrodecyl) -triethoxysilane, (heptadecafluoro-1,1,2,2-tetra Hydrodecyl) -trimethoxysilane, 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane, 1H, 1H, 2H, 2H-perfluorooctyltrimethoxysilane, 3,3,3-tri Fluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxysilane, hexadecafluorododec-11-ene-1-yltrimethoxysilane, hexadecafluorododec-11-ene One or more selected from the group consisting of -1-yltriethoxysilane may be used, but is not necessarily limited thereto.

The organosilanol or organoalkoxysilane having the symmetrical structure may be used by selecting one or more from the following Chemical Formula 3 or Chemical Formula 4. The organosilanol or organoalkoxysilane has an organic chain substituted with two hydroxyl groups or two alkoxy groups and a functional group or an unsubstituted functional chain.

 (3)

[In Formula 3, R ⁵ is (C1-C20) alkyl, (C3-C8) cycloalkyl, (C3-C8) alkyl substituted with (C3-C8) cycloalkyl, (C2-C20) alkenyl, ( C2 ~ C20) alkynyl and (C6 ~ C20) aryl.

[Formula 4]

[R ⁶ in Formula 4 Silver (C1-C20) alkyl, (C3-C8) cycloalkyl, (C3-C8) alkyl substituted with (C3-C8) cycloalkyl, (C2-C20) alkenyl, (C2-C20) alkynyl and ( C6 ~ C20) aryl; R ⁷ is straight or branched chain (C 1 -C ⁷ ) alkyl.]

More specifically, the organosilanol or organoalkoxysilane having the symmetrical structure may include diphenylsilanediol, diisobutylsilanediol, diphenyldimethoxysilane, diphenyldiethoxysilane, diisobutyldimethoxysilane. , But may be used one or more selected from the group consisting of diisobutyl diethoxysilane, but is not necessarily limited thereto.

In the present invention, when the fluorinated organic oligosiloxane is prepared by a sol-gel reaction between a mixture of an organoalkoxysilane having an asymmetrical structure and an alkoxy fluoride having an asymmetric structure and an organosilane or an organoalkoxysilane having a symmetrical structure, The amount of the alkoxy fluoride silane relative to the total silane amount is preferably 1 to 30 mol%. More preferably, the amount of the alkoxy fluoride silane relative to the total amount of silane is preferably used in 20 to 30 mol%. When the amount of the alkoxysilane fluoride in the fluorinated organoligosiloxane is too small, the fluoro group for reducing the electron polarization is reduced, so that the dielectric constant of the low dielectric constant siloxane protective film composition is low. In addition, when the amount of the alkoxysilane fluoride in the fluorinated organoligosiloxane is too large, it is difficult to obtain a transparent fluorinated organoligosiloxane due to too many fluoro groups, thereby lowering the transparency of the low dielectric constant siloxane protective film composition.

In addition, the amount of organosilanol or organic alkoxysilane having a symmetrical structure with respect to the total amount of silane is preferably 30 to 60 mol%. More preferably, the amount of organosilanol or organic alkoxysilane relative to the total amount of silane is 50 to 60 mol%. When the amount of symmetrical organoolol or organic alkoxysilane in the fluorinated organoligosiloxane is reduced, the ratio of the organic alkoxysilane having an asymmetric structure with a large dipole moment is increased to increase the dielectric constant. In addition, if the amount of symmetrical organic silanol or organic alkoxysilane is too large in the fluorinated organic oligosiloxane, the synthesized fluorinated organic oligosiloxane may become opaque, resulting in low transparency of the low dielectric constant siloxane protective film composition.

The present invention relates to a siloxane protective film composition comprising a fluorinated organic oligosiloxane prepared by the above production method.

More specifically, the siloxane protective film composition of the present invention may further include any one or more selected from a solvent, a thermosetting catalyst or a photocuring catalyst, a monomer having a functional group, a curing agent, and a crosslinking agent in the fluorinated organic oligosiloxane.

When the solvent is added in the present invention, the viscosity of the siloxane protective film composition is controlled and the coating thickness is controlled. The solvent may be added in the process of preparing the fluorinated organoligosiloxane, or may be added after the organoligosiloxane is prepared. The solvent is an aliphatic hydrocarbon solvent such as hexane and heptane; Ketone solvents such as methyl isobutyl ketone, 1-methyl-2-pyrrolidinone, cyclohexanone and acetone; Ether solvents such as tetrahydrofuran, isopropyl ether and propylene glycol propyl ether; Acetate solvents such as ethyl acetate, butyl acetate and propylene glycol methyl ether acetate; Alcohol solvents such as isopropyl alcohol and butyl alcohol; Amide solvents such as dimethylacetamide and dimethylformamide; And one or more selected from the group consisting of a silicone solvent may be used, but is not necessarily limited thereto.

The fluorinated organooligosiloxane of the present invention may include thermosetting functional groups or photocurable functional groups. In this case, the fluorinated organic oligosiloxane is prepared through a step of thermosetting or photocuring to form a more uniform and dense low dielectric constant siloxane protective film. In order to prepare a low dielectric constant siloxane protective film comprising a fluorinated organic oligosiloxane including the thermosetting functional group or a photocurable functional group, the organic alkoxysilane or the organic group of organosilanol must have a thermosetting functional group or a photocurable functional group. . The thermosetting functional group or photocurable functional group is an epoxy group, an alicyclic epoxy group, an acrylic group, a methacryl group, a vinyl group, an amino group, a hydroxyl group, or the like.

In addition, when the fluorinated organic oligosiloxane has a thermosetting functional group or a photocurable functional group, a thermosetting catalyst or a photocuring catalyst may be further added.

The thermosetting catalyst is an amine series such as benzyl dimethyl amine; Imidazole series such as 1-methylimidazole and 2-phenylimidazole; Phosphorus series such as triphenylphosphine, triphenylphosphate, trioctylphosphine, tri tert-butylphosphine and tert-butylphosphonium methane supporton; Aluminum Acetyl Acetonate (Alacac), Platinum (0) -1,3-Divinyl-1,1,3,3-tetramethyldisiloxane Complex Solution, Xylene Platinum (~ 2%), Platinum-Cyclovinylmethylsiloxane Metal catalysts, such as a complex and a tris (dibutylsulfide) rhodium trichloride, can be used.

The photocuring catalyst is aryl sulfonium hexafluoro antimony salt, 2,2-dimethoxy-2-phenyl acetophenone, benzoyl peroxide, dicumyl peroxide, benzoyl peroxide, 2,2-azobis -(2-methyl propionitrile) and the like can be used, but is not necessarily limited thereto.

In addition, when the fluorinated organoligosiloxane has a thermosetting or photocurable functional group, addition of a curing agent and a crosslinking agent exhibits excellent thermal, mechanical and thermomechanical properties. Examples of the curing agent and crosslinking agent include an acid anhydride curing agent, a phenol curing agent, an amine curing agent, a mercapto curing agent, and an organohydrogensilicon crosslinking agent. The content of the curing agent and the crosslinking agent is preferably added in the range of 1: 1 to 1: 1.5 in equivalent ratio of the fluorinated organoligosiloxane and the curing agent and the crosslinking agent.

In addition, when the fluorinated organoligosiloxane has a thermosetting functional group or a photocurable functional group, a monomer having a thermosetting functional group or a photocurable functional group can be added. The said monomer can be used 1 type or in mixture of 2 or more types different from each other. Specifically, for example, 2,2,3,3,4,4,5,5-octafluoro-1,6-hexanediol diacrylate as a monomer having a thermosetting functional group or a photocurable functional group, 1 , 4-butanediol diacrylate, 1,6-hexanediol diacrylate, ethylene glycol diacrylate, 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane-carboxylate, 2-ethyl Hexyl oxetane, 3-ethyl-3 [[(3-ethyloxetan-3-yl) methoxy] methyl] oxetane, and the like can be used, but is not necessarily limited thereto. By adding the monomer, the density of the siloxane protective film composition, the free volume, the adhesion to the substrate, the dielectric constant, the insulating properties, and the like can be adjusted, and the thermal stability of the siloxane protective film composition is improved. The content is preferably 1 to 30 parts by weight based on 100 parts by weight of the fluorinated organic oligosiloxane. When too much monomer is added, the inorganic part is reduced, resulting in poor insulation and higher dielectric constant. Also, thermal stability tends to be reduced.

In addition, when the fluorinated organic oligosiloxane including a thermosetting functional group or a photocurable functional group undergoes a step of thermosetting or photocuring, the step may be subjected to a heat treatment step after the step. By performing the heat treatment, impurities can be removed, thereby achieving high thermal stability, and minimizing degassing of device properties by minimizing outgassing of the film. The heat treatment step may be carried out at 200 ° C or less, specifically, 50 to 200 ° C. The heat treatment step is preferably carried out at 150 ℃ or less, specifically 50 to 150 ℃. When the temperature of the heat treatment step is a high temperature of 200 ℃ or more, it can break the bond chain of the organic functional period, and if it is too low, it may be difficult to remove the additionally added solvent.

In general, the protective film of the thin film transistor should have a low dielectric constant in order to prevent signal delay between the wirings of the display, and high flatness which contributes to high transparency and improved aperture ratio is essential for realizing a high resolution and high brightness display. In order to replace inorganic protective films such as silicon nitride and silicon oxide by vacuum deposition, they must have high thermal stability, low leakage current characteristics and high adhesion characteristics. In addition, low temperature solution processing should be possible to cope with large area display substrates. Since the low dielectric constant siloxane protective film of this invention satisfy | fills all the said conditions, it is suitable as a protective film of a thin film transistor.

The low dielectric constant siloxane protective film composition for the passivation layer of the thin film transistor containing the fluorinated organic oligosiloxane of the present invention has excellent insulation properties, thermal stability, and high transparency by nano-sized oligosiloxane formed by sol-gel reaction. It has a low dielectric constant of 3.0 or less by organosilanol and organic alkoxysilane having a symmetrical structure with the fluorine group of the alkoxy fluoride silane.

In addition, the organic functional group of the organic alkoxysilane enables low temperature and solution process, and has excellent flatness and adhesive properties. As a result, the low dielectric constant siloxane protective film composition has characteristics of low dielectric constant, excellent insulation, high transparency, excellent thermal stability, flatness, adhesiveness, low temperature, and solution process, and is suitable as a passivation layer of a thin film transistor.

Fig. 1 shows a low dielectric constant siloxane protective film for a protective film of a thin film transistor according to the third embodiment of the present invention.

The invention is illustrated by the following examples. However, these do not limit the technical scope of the present invention.

&Lt; Example 1 >

2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (ECTMS, Gelest): (heptadecafluoro-1,1,2,2-tetrahydrodecyl) -trimethoxysilane (PFAS, Gelest) Co., Ltd .: Diphenylsilanediol (DPSD, Gelest Co., Ltd.) was mixed in a ratio of 4.93 g: 17.05 g: 10.82 g (0.02 mol: 0.03 mol: 0.05 mol) and placed in a 100 ml 2neck flask. Thereafter, 0.02 g (0.1 mol% of silane) barium hydroxide was added as a catalyst to the mixture, which was stirred at 80 ° C. under N 2 nitrogen purge for 4 hours. The resin obtained after 4 hours of sol-gel reaction was filtered using a 0.45um Teflon filter to obtain a fluorinated alicyclic epoxy oligosiloxane resin. Next, 125 parts by weight of propylene glycol methyl ether acetate (PGMEA, Aldrich) is added as a solvent, and 4 parts by weight of aryl sulfonium hexafluoro antimony salt (Aldrich) is used as a photocuring catalyst. After addition, it was stirred for 3 hours.

After the stirred resin was formed into a film by spin coating on a glass substrate on which ITO was deposited, the prepared sample was photocured by exposing the prepared sample to an ultraviolet lamp having a wavelength of 365 nm for 1 minute. After the photocuring, the thermal curing was performed for 2 hours at a temperature of 150 ℃. 35 nm of gold electrodes were deposited on the formed film using thermal evaporation and shadow mast.

<Example 2>

2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (ECTMS, Gelest): (heptadecafluoro-1,1,2,2-tetrahydrodecyl) -trimethoxysilane (PFAS, Gelest) Co., Ltd .: Diphenyldimethoxysilane (DPDMS, Aldrich Co., Ltd.) was mixed in a ratio of 4.93 g: 17.05 g: 10.82 g (0.02 mol: 0.03 mol: 0.05 mol) and placed in a 100 ml 1neck flask. Thereafter, 2.7 g of water was added to the mixture, and 1 g of Amberite IPA-400 (Cl) (Aldrich) was added as a catalyst and stirred under reflux at 80 ° C. for 24 hours. The resin obtained after the sol-gel reaction for 24 hours was removed by using a reduced pressure evaporator to remove water and methanol in the resin at a pressure of -0.1 MPa and a temperature of 60 ° C. After filtration using a 0.45um Teflon filter to give a fluorinated alicyclic epoxy oligosiloxane resin. Next, 150 parts by weight of propylene glycol methyl ether acetate (PGMEA, Aldrich) was added as a solvent, and 4 parts by weight of aryl sulfonium hexafluoro antimony salt (Aldrich) was used as a photocuring catalyst. After addition, it was stirred for 3 hours.

After the stirred resin was formed into a film by spin coating on a glass substrate on which ITO was deposited, the prepared sample was photocured by exposing the prepared sample to an ultraviolet lamp having a wavelength of 365 nm for 1 minute. After the photocuring, the thermal curing was performed for 2 hours at a temperature of 150 ℃. 35 nm of gold electrodes were deposited on the formed film using thermal evaporation and shadow mast.

<Example 3>

3-methacrylopropyltrimethoxysilane (MPTMS, Aldrich): heptadecafluoro-1,1,2,2-tetrahydrodecyl) -trimethoxysilane (PFAS, Gelest): diphenylsilanediol (DPSD, Gelest, Inc.) was mixed with 4.97 g: 11.27 g: 12.98 g (0.02 mol: 0.02 mol: 0.06 mol) and placed in a 100 ml 2neck flask. Thereafter, 0.02 g (0.1 mol% of silane) barium hydroxide was added as a catalyst to the mixture, followed by stirring at 80 ° C. for 4 hours under N 2 nitrogen purge. The resin obtained after 4 hours of sol-gel reaction was filtered using a 0.45 um Teflon filter to obtain a fluorinated methacryloligosiloxane resin. Next, 100 parts by weight of propylene glycol methyl ether acetate (PGMEA, Aldrich) is added to the resin, and 2,2-dimethoxy-2-phenyl acetophenone (BDK, Aldrich) is used as the photocuring catalyst. After the addition of 2 parts by weight, the mixture was stirred for 3 hours.

After the stirred resin was formed into a film by spin coating on the glass substrate on which ITO was deposited, the prepared sample was photocured by exposing the prepared sample to an ultraviolet lamp having a wavelength of 365 nm for 3 minutes. After the photocuring, the thermal curing was performed for 2 hours at a temperature of 150 ℃. 35 nm of gold electrodes were deposited on the formed film using thermal evaporation and shadow mast.

<Example 4>

3-methacrylopropyltrimethoxysilane (MPTMS, Aldrich): heptadecafluoro-1,1,2,2-tetrahydrodecyl) -trimethoxysilane (PFAS, Gelest): diphenylsilanediol (DPSD, Gelest, Inc.) was mixed in a ratio of 4.97 g: 11.37 g: 12.98 g (0.02 mol: 0.02 mol: 0.06 mol) and placed in a 100 ml 1neck flask. Then 2.7 g of water with HCl 0.5N concentration was added to the mixture and stirred at 80 ° C. under reflux for 24 hours. The resin obtained after the sol-gel reaction for 24 hours was removed by using a reduced pressure evaporator to remove water and methanol in the resin at a pressure of -0.1 MPa and a temperature of 60 ° C. Thereafter, the resultant was filtered using a 0.45 um Teflon filter to obtain a fluorinated methacrylate oligosiloxane resin. Next, 100 parts by weight of propylene glycol methyl ether acetate (PGMEA, Aldrich) is added to the resin, and 2,2-dimethoxy-2-phenyl acetophenone (BDK, Aldrich) is used as the photocuring catalyst. After the addition of 2 parts by weight, the mixture was stirred for 3 hours.

After the stirred resin was formed into a film by spin coating on the glass substrate on which ITO was deposited, the prepared sample was photocured by exposing the prepared sample to an ultraviolet lamp having a wavelength of 365 nm for 3 minutes. After the photocuring, the thermal curing was performed for 2 hours at a temperature of 150 ℃. 35 nm of gold electrodes were deposited on the formed film using thermal evaporation and shadow mast.

Example 5

3-methacrylopropyltrimethoxysilane (MPTMS, Aldrich): heptadecafluoro-1,1,2,2-tetrahydrodecyl) -trimethoxysilane (PFAS, Gelest): diphenylsilanediol (DPSD, Gelest, Inc.) was mixed with 4.97 g: 11.27 g: 12.98 g (0.02 mol: 0.02 mol: 0.06 mol) and placed in a 100 ml 2neck flask. Thereafter, 0.02 g (0.1 mol% of silane) barium hydroxide was added as a catalyst to the mixture, followed by stirring at 80 ° C. for 4 hours under N 2 nitrogen purge. The resin obtained after 4 hours of sol-gel reaction was filtered using a 0.45 um Teflon filter to obtain a fluorinated methacryloligosiloxane resin. 2,2,3,3,4,4,5,5-octafluoro-1,6-hexanediol diacrylate (TCI Co., Ltd.) as a monomer having a photocurable functional group in the synthesized resin 10 weight Part added.

Next, 75 parts by weight of propylene glycol methyl ether acetate (PGMEA, Aldrich) was added as a solvent, and 2,2-dimethoxy-2-phenyl acetophenone (BDK, Aldrich) was used as a photocuring catalyst. After the addition of 2 parts by weight, the mixture was stirred for 3 hours.

After the stirred resin was formed into a film by spin coating on the glass substrate on which ITO was deposited, the prepared sample was photocured by exposing the prepared sample to an ultraviolet lamp having a wavelength of 365 nm for 3 minutes. After the photocuring, the thermal curing was performed for 2 hours at a temperature of 150 ℃. 35 nm of gold electrodes were deposited on the formed film using thermal evaporation and shadow mast.

<Example 6>

2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (ECTMS, Gelest): (heptadecafluoro-1,1,2,2-tetrahydrodecyl) -trimethoxysilane (PFAS, Gelest) Co., Ltd .: Diphenylsilanediol (DPSD, Gelest Co., Ltd.) was mixed in a ratio of 4.93 g: 17.05 g: 10.82 g (0.02 mol: 0.03 mol: 0.05 mol) and placed in a 100 ml 2neck flask. Thereafter, 0.02 g (0.1 mol% of silane) barium hydroxide was added as a catalyst to the mixture, which was stirred at 80 ° C. under N 2 nitrogen purge for 4 hours. The resin obtained after 4 hours of sol-gel reaction was filtered using a 0.45um Teflon filter to obtain a fluorinated alicyclic epoxy oligosiloxane resin. To the synthesized resin, tetrafluorophthalic anhydride (TCI Co., Ltd.) as a thermosetting agent was added in an amount ratio of 1: 1 to the resin content. 100 parts by weight of propylene glycol methyl ether acetate (PGMEA, Aldrich) was added as a solvent, and 0.5 mol% of tert-butylphosphonium methane sulfonate was added as a thermosetting catalyst, followed by stirring for 3 hours.

After the stirred resin was formed into a film by spin coating on the glass substrate on which ITO was deposited, the prepared sample was thermally cured at a temperature of 150 ° C. for 2 hours. 35 nm of gold electrodes were deposited on the formed film using thermal evaporation and shadow mast.

Comparative Example 1

2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (ECTMS, Gelest): diphenylsilanediol (DPSD, Gelest, Inc.) at 12.32 g: 10.82 g (0.05 mol: 0.05 mol) Into a 100 ml 2neck flask. Thereafter, 0.02 g (0.1 mol% of silane) barium hydroxide was added as a catalyst to the mixture, which was stirred at 80 ° C. under N 2 nitrogen purge for 4 hours. The resin obtained after 4 hours of sol-gel reaction was filtered using a 0.45um Teflon filter to obtain an alicyclic epoxy oligosiloxane resin. Next, 100 parts by weight of propylene glycol methyl ether acetate (PGMEA, Aldrich) was added as a solvent, and 4 parts by weight of aryl sulfonium hexafluoro antimony salt was added as a photocuring catalyst. Stir for 3 hours.

After the stirred resin was formed into a film by spin coating on a glass substrate on which ITO was deposited, the prepared sample was photocured by exposing the prepared sample to an ultraviolet lamp having a wavelength of 365 nm for 1 minute. After the photocuring, the thermal curing was performed for 2 hours at a temperature of 150 ℃. 35 nm of gold electrodes were deposited on the formed film using thermal evaporation and shadow mast.

Comparative Example 2

3-methacrylopropyltrimethoxysilane (MPTMS, Aldrich): Diphenylsilanediol (DPSD, Gelest, Inc.) was mixed with 9.93 g: 12.98 g (0.04 mol: 0.06 mol) and placed in a 100 ml 2neck flask. Thereafter, 0.02 g (0.1 mol% of silane) barium hydroxide was added as a catalyst to the mixture, followed by stirring at 80 ° C. for 4 hours under N 2 nitrogen purge. The resin obtained after 4 hours of sol-gel reaction was filtered using a 0.45 um Teflon filter to obtain a fluorinated methacryloligosiloxane resin. Next, 100 parts by weight of propylene glycol methyl ether acetate (PGMEA, Aldrich) was added as a solvent, and 2,2-dimethoxy-2-phenyl acetophenone (BDK, Aldrich) was used as a photocuring catalyst. After the addition of 2 parts by weight, the mixture was stirred for 3 hours.

After the stirred resin was formed into a film by spin coating on the glass substrate on which ITO was deposited, the prepared sample was photocured by exposing the prepared sample to an ultraviolet lamp having a wavelength of 365 nm for 3 minutes. After the photocuring, the thermal curing was performed for 2 hours at a temperature of 150 ℃. 35 nm of gold electrodes were deposited on the formed film using thermal evaporation and shadow mast.

&Lt; Comparative Example 3 &

19.87 g of 3-methacrylopropyltrimethoxysilane (MPTMS, Aldrich) and heptadecafluoro-1,1,2,2-tetrahydrodecyl) -trimethoxysilane (PFAS, Gelest): 11.37 g (0.08 mol: 0.02 mol) was mixed in a ratio of 100ml 1neck flask. Then 2.7 g of water with HCl 0.5N concentration was added to the mixture and stirred at 80 ° C. under reflux for 24 hours. The resin obtained after the sol-gel reaction for 24 hours was removed by using a reduced pressure evaporator to remove water and methanol in the resin at a pressure of -0.1 MPa and a temperature of 60 ° C. After filtration using a 0.45 um Teflon filter to obtain a symmetric organoalkoxysilane or fluorinated methacryloligosiloxane resin without organosilanol. Next, 100 parts by weight of propylene glycol methyl ether acetate (PGMEA, Aldrich) was added as a solvent, and 2,2-dimethoxy-2-phenyl acetophenone (BDK, Aldrich) was used as a photocuring catalyst. After the addition of 2 parts by weight, the mixture was stirred for 3 hours.

After the stirred resin was formed into a film by spin coating on the glass substrate on which ITO was deposited, the prepared sample was photocured by exposing the prepared sample to an ultraviolet lamp having a wavelength of 365 nm for 3 minutes. After the photocuring, the thermal curing was performed for 2 hours at a temperature of 150 ℃. 35 nm of gold electrodes were deposited on the formed film using thermal evaporation and shadow mast.

<Test Example>

The physical properties of the samples obtained in the above examples were evaluated in the following manners, and the results are shown in Tables 1 to 1.

[permittivity]

The dielectric constant at 1 MHz was measured using a Cf curve obtained using HP's HP4194A.

[Leakage current]

Leakage current at 1 MV / cm was measured using an IV curve obtained using Keithley's keithley237.

 [Transmittance]

Transmittance was measured at 550 nm wavelength using a UV / VIS / NIR spectrum analyzer UV-3101PC from Shimadzu Corporation.

[Thermal stability]

Thermogravimetric analysis (TGA) from TA was used to measure the thermal decomposition in a nitrogen atmosphere and then 5% loss temperature.

[Flatness and adhesiveness]

After spin coating the fluorinated oligosiloxane resin of Example 3 onto a patterned substrate, the cut surface was measured by a scanning electron microscope (SEM).

Table 1 Properties of low dielectric constant siloxane protective films for thin film transistors

Table 1 shows the dielectric constant, leakage current, transmittance, and thermal stability of the low dielectric constant siloxane protective film composition for protective films of the thin film transistors of Examples 1 to 6. In addition, in Table 1, Comparative Example 1 and Comparative Example 2 showed the dielectric constant, leakage current, transmittance, thermal stability of the composition when the organic alkoxy fluoride silane having an asymmetric structure was not added. Comparative Example 3 showed the dielectric constant, leakage current, transmittance, and thermal stability of the composition when the organosilanol and organoalkoxysilane having a symmetric structure were not added. Comparing Example 1, Example 2, and Comparative Example 1, and comparing Example 3, Example 4, and Comparative Example 2, the dielectric constant is lowered to 3.0 or less and leakage current is reduced by addition of an asymmetric organic alkoxy fluoride silane. 10 nA / cm ² The transmittance is 95% or more, and the thermal stability is increased by 30 to 50 ° C. In addition, when comparing Example 4 and Comparative Example 3, the addition of the organoalkoxysilane and the organic silanol having a symmetric structure lowered the dielectric constant below 3.0 and the leakage current was 10 nA / cm ^2. To lower below. In addition, when comparing Example 3 and Example 5, the addition of a photocurable monomer in the same composition was confirmed that the other properties do not change and the thermal stability increased by 30 ℃. This is due to the crosslinking density with monomer addition. Comparing Example 1 and Example 6, when the thermosetting agent and the thermosetting catalyst were added, it was confirmed that other properties did not change and the thermal stability increased by 30 ° C. This is due to the crosslinking density due to the thermoset and thermoset catalyst.

FIG. 1 is a SEM photograph when the protective film is formed on a patterned substrate by spin coating with the low dielectric constant siloxane protective film composition of Example 3. FIG. The low dielectric constant siloxane protective film composition has excellent adhesion to metals and oxides such as Al, and has excellent planarization properties. In addition, as a result of the above examples and comparative examples, the low dielectric constant siloxane protective film composition according to the present invention has the characteristics of high transparency, excellent thermal stability, low dielectric constant, low leakage current, flatness, adhesiveness to use as a protective film of a thin film transistor Ideal for

Claims (17)

By the sol-gel reaction of an organoalkoxysilane having an asymmetric structure of Formula 1, an alkoxy fluoride silane having an asymmetric structure of Formula 2 and a silane mixture containing an organoalkoxysilane having a symmetric structure of Formula 4 Low dielectric constant siloxane protective film composition for a protective film of a thin film transistor comprising a fluorinated organic oligosiloxane prepared:
[Formula 1]

(2)

[Chemical Formula 4]

In the above formula
R ¹ is (C ¹ -C 20) alkyl, (C 3 -C 8) cycloalkyl, (C 3 -C 8) alkyl substituted with (C 3 -C 8) cycloalkyl, (C 2 -C 20) alkenyl, (C 2 -C 20) alkynyl Or (C6-C20) aryl;
R ¹ is an acryl group, methacryl group, aryl group, amino group, mercapto group, ether group, ester group, sulfone group, nitro group, hydroxy group, cyclobutene group, carbonyl group, carboxyl group, alkyd group, urethane group, vinyl May have one or more functional groups selected from the group consisting of groups, nitrile groups, epoxy groups and alicyclic epoxy groups;
R ³ is (C 1 -C 20) alkyl containing a fluoro group, (C 3 -C 8) cycloalkyl, (C 1 -C 20) alkyl substituted with (C 3 -C 8) cycloalkyl, (C 2 -C 20) alkenyl, (C 2 C20) alkynyl or (C6-C20) aryl;
R ⁶ is (C 1 -C 20) alkyl, (C 3 -C 8) cycloalkyl, (C 3 -C 8) alkyl substituted with (C 3 -C 8) cycloalkyl, (C 2 -C 20) alkenyl, (C 2 -C 20) alkynyl Or (C6-C20) aryl;
R ² , R ⁴ and R ⁷ are straight or branched chain (C 1 -C ⁷ ) alkyl. The method of claim 1,
A low dielectric constant siloxane protective film composition for a protective film of a thin film transistor comprising a fluorinated organic oligosiloxane having 1 to 30 mol% of an alkoxy fluoride silane relative to the silane mixture. The method of claim 1,
A low dielectric constant siloxane protective film composition for a protective film of a thin film transistor comprising a fluorinated organic oligosiloxane having 30 to 60 mol% of an organic silanol or an organic alkoxysilane having a symmetrical structure with respect to the silane mixture. delete delete delete The method of claim 1,
The asymmetric organoalkoxysilanes include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3 , 4-epoxycyclohexyl) ethyltriethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, propylethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, Vinyltriethoxysilane, aryltrimethoxysilane, aryltriethoxysilane, vinyltripropoxysilane, phenyltrimethoxysilane, N- (3-acryloxy-2-hydroxypropyl) -3-aminopropyltri Ethoxysilane, N- (3-acryloxy-2-hydroxypropyl) -3-aminopropyltrimethoxysilane, N- (3-acryloxy-2-hydroxypropyl) -3-aminopropyltripropoxy Silane, (acryloxymethyl) phenethyltrimethoxysilane, N- (aminoethyl) -3-aminopropyl trimethoxy Column, N- (2-aminoethyl) -3-aminopropyl triethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, chloropropyltrimethoxysilane, chloropropyltriethoxy A low dielectric constant siloxane protective film composition for protective films of a thin film transistor comprising a fluorinated organic oligosiloxane selected from the group consisting of silane, phenyltrimethoxysilane and phenyltriethoxysilane. The method of claim 1,
The asymmetrical alkoxysilane silane is (heptadecafluoro-1,1,2,2-tetrahydrodecyl) -triethoxysilane or (heptadecafluoro-1,1,2,2-tetrahydrodecyl)- A low dielectric constant siloxane protective film composition for protective films of a thin film transistor containing a fluorinated organic oligosiloxane which is trimethoxysilane. The method of claim 1,
The organoalkoxysilane having the symmetrical structure is at least one fluorinated organic oligo group selected from the group consisting of diphenyldimethoxysilane, diphenyldiethoxysilane, diisobutyldimethoxysilane and diisobutyldiethoxysilane. Low dielectric constant siloxane protective film composition for protective films of thin film transistors containing siloxane. The method of claim 1,
The sol-gel reaction is a low dielectric constant siloxane protective film composition for a protective film of a thin film transistor comprising a fluorinated organic oligosiloxane carried out in the presence of an acid catalyst, a base catalyst or an ion exchange resin catalyst. The method of claim 1,
A low dielectric constant siloxane protective film composition for a protective film of a thin film transistor comprising a fluorinated organic oligosiloxane which adds a thermosetting catalyst or a photocuring catalyst to the fluorinated organic oligosiloxane. The method of claim 1,
A low dielectric constant siloxane protective film composition for protective films of a thin film transistor comprising a fluorinated organic oligosiloxane in which a curing agent and a crosslinking agent are added to the fluorinated organic oligosiloxane. The method of claim 1,
A low dielectric constant siloxane protective film composition for protective films of a thin film transistor comprising a fluorinated organic oligosiloxane containing a thermosetting functional group or a monomer having a photocurable functional group in the fluorinated organic oligosiloxane. The method of claim 1,
A low dielectric constant siloxane protective film composition for protective films of a thin film transistor comprising a fluorinated organic oligosiloxane, wherein the fluorinated organic oligosiloxane contains a solvent. Claims 1 to 3 and 7 to 14 wherein the composition of any one selected from fluorinated organoligosiloxane, characterized in that the thermal curing or photocuring, and undergoing a heat treatment step at 50 to 200 ℃ Low dielectric constant siloxane protective film composition for protective films of thin film transistors. The thin film transistor using the low dielectric constant siloxane protective film composition of any one of Claims 1-3 and 7-14. The thin film transistor using the low dielectric constant siloxane protective film composition of Claim 15.

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